Organic electro-luminescent device and method for fabricating the same

Abstract

An organic electro-luminescent device with an optical compensation layer comprising a substrate comprising a first device region and a second device region, a first diode, and a second diode. The first diode is disposed in the first device region and the second diode in the second device region. Each diode comprises an anode, an opposing transparent cathode, and an organic electro-luminescent medium layer sandwiched therebetween. The transparent cathode in the first device region has a thickness substantially equal to that in the second device region. An optical layer is adjacent to the transparent cathode in the first device region, serving as the optical compensation layer to form cathodes with different thicknesses in first and second device regions, respectively. Methods for fabricating an organic electro-luminescent device are also disclosed.

1 . An organic electro-luminescent device, comprising: 
 a substrate comprising a first device region and a second device region;    a first anode and an opposing first transparent cathode disposed in the first device region;    a first organic electro-luminescent medium layer sandwiched between the first anode and the first transparent cathode;    a first optical layer adjacent to the first transparent cathode;    a second anode and an opposing second transparent cathode disposed in the second device region; and    a second organic electro-luminescent medium layer sandwiched between the second anode and the second transparent cathode;    wherein the first transparent cathode has a thickness substantially equal to the second transparent cathode.    
   
   
       2 . The device as claimed in  claim 1 , wherein the first optical layer is disposed on the first transparent cathode.  
   
   
       3 . The device as claimed in  claim 2 , further comprising a second optical layer disposed on the second transparent cathode, having a thickness different from that of first optical layer.  
   
   
       4 . The device as claimed in  claim 1 , wherein the first optical layer is sandwiched between the first transparent cathode and the first organic electro-luminescent medium layer.  
   
   
       5 . The device as claimed in  claim 4 , further comprising a second optical layer sandwiched between the second transparent cathode and the second organic electro-luminescent medium layer, having a thickness different from that of first optical layer.  
   
   
       6 . The device as claimed in  claim 1 , wherein the transmittance of the first optical layer for visible light is greater than 40%.  
   
   
       7 . The device as claimed in  claim 1 , wherein the refraction index of the first optical layer is great than or equal to 2.  
   
   
       8 . The device as claimed in  claim 1 , wherein the first transparent cathode has a thickness of 5 to 1000 Å.  
   
   
       9 . The device as claimed in  claim 8 , wherein the first optical layer has a thickness of 5 to 1000 Å.  
   
   
       10 . The device as claimed in  claim 1 , wherein the first and second anodes further comprise an opaque layer serving as a reflective layer.  
   
   
       11 . A method for fabricating an electro-luminescent device, comprising: 
 providing a substrate comprising a first device region and a second device region;    respectively forming an anode in the first and second device regions;    forming an organic electro-luminescent medium layer on each anode;    forming a transparent cathode on each organic electro-luminescent medium layer; and    forming a first optical layer adjacent to the transparent cathode in the first device region.    
   
   
       12 . The method as claimed in  claim 11 , wherein the first optical layer is formed on the transparent cathode in the first device region.  
   
   
       13 . The method as claimed in  claim 12 , further forming a second optical layer on the transparent cathode in the second device region, having a thickness different from that of the first optical layer.  
   
   
       14 . The method as claimed in  claim 11 , wherein the first optical layer is formed between the transparent cathode and the organic electro-luminescent medium layer in the first device region.  
   
   
       15 . The method as claimed in  claim 14 , further forming a second optical layer between the transparent cathode and the organic electro-luminescent medium layer in the second device region, having a thickness different from that of the first optical layer.  
   
   
       16 . The method as claimed in  claim 11 , wherein the transmittance of the first optical layer for visible light is greater than 40%.  
   
   
       17 . The method as claimed in  claim 11 , wherein the refraction index of the first optical layer is great than or equal to 2.  
   
   
       18 . The method as claimed in  claim 11 , wherein the anode further comprise an opaque layer serving as a reflective layer.  
   
   
       19 . The method as claimed in  claim 11 , wherein the first optical layer is formed at a temperature below 70° C.  
   
   
       20 . The method as claimed in  claim 11 , wherein the first optical layer is formed by E-beam deposition, thermal evaporation, molecular beam epitaxy, vapor phase epitaxy, or metal organic chemical vapor deposition.